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TC 17/SC 7: Breath Alcohol Analysers
August 2007
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Date: 20 April 2007
Reference number: ……….
Supersedes document: OIML R 126- CD2
OIML TC 17 / SC 7
Title:
OIML R 126 Breath alcohol analysers
Secretariat:
TC 17/SC 7:
Circulated to P- and O-members and
liaison international bodies and external
organisations for:
discussion planned at a meeting to be held
on April 2008 (to be confirmed)........
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vote (P-members only) and comments by
TITLE OF THE CD (English):
Revision OIML R 126
Breath alcohol analysers
TITLE OF THE CD (French):
Ethylomètres
Original version in: English
3rd Committee Draft Recommendation on Breath Alcohol Analysers
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TC 17/SC 7: Breath Alcohol Analysers
TC 17 / SC 7
August 2007
SECRETARIAT: FRANCE
P-Members:
AUSTRALIA
AUSTRIA
BELGIUM
BRAZIL
FRANCE
GERMANY
NETHERLANDS
NORWAY
POLAND
ROMANIA
RUSSIAN FEDERATION
UNITED KINGDOM
UNITED STATES
O-Members:
BULGARIA
CANADA
CZECH REPUBLIC
DENMARK
FINLAND
HUNGARY
IRELAND
JAPAN
SERBIA AND MONTENEGRO
SLOVAKIA
SLOVENIA
SWEDEN
SWITZERLAND
Liaisons:
IEC, International Electrotechnical Commission
ISO, International Organization for Standardization
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August 2007
CONTENT
Requirements........................................................................................................................................... 6
1
Scope ........................................................................................................................................... 6
2
Terminology ................................................................................................................................ 6
2.1 Breath alcohol analyser ........................................................................................................... 6
2.2 Stationary breath alcohol analyser........................................................................................... 6
2.3 Mobile breath alcohol analyser ............................................................................................... 6
2.4 Portable breath alcohol analyser.............................................................................................. 7
2.5 Alveolar air.............................................................................................................................. 7
2.6 End expiratory breath .............................................................................................................. 7
2.7 dead anatomical volume .......................................................................................................... 7
2.8 Measuring mode ...................................................................................................................... 7
2.9 Maintenance mode .................................................................................................................. 7
3
2.10
Stand by mode ..................................................................................................................... 7
2.11
Adjustment device............................................................................................................... 7
2.12
Fault (OIML D11-3.9)......................................................................................................... 7
2.13
Significant fault (OIML D11-3.10) ..................................................................................... 7
2.14
Disturbances ........................................................................................................................ 7
2.15
Built-in automatic checking facility .................................................................................... 8
2.16
Drift ..................................................................................................................................... 8
2.17
Memory residual effect ....................................................................................................... 8
Metrological requirements .......................................................................................................... 8
3.1 Reliability of the measurement................................................................................................ 8
3.2 Rated operating conditions ...................................................................................................... 8
1.3 Maximal permissible errors (MPE) ......................................................................................... 9
1.4 Disturbances and other influence quantities.......................................................................... 10
1.5 Estimation of the repeatability............................................................................................... 10
1.6 Drift ....................................................................................................................................... 11
1.7 Memory and residual effect................................................................................................... 11
1.8 Durability .............................................................................................................................. 11
4
Technical requirements ............................................................................................................. 11
4.1 Physical quantity and unit of measurement........................................................................... 11
4.2 Display .................................................................................................................................. 12
4.3 Printing device....................................................................................................................... 12
4.4 Measuring conditions ............................................................................................................ 13
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August 2007
4.5 Checking operations .............................................................................................................. 13
4.6 Suitability for use .................................................................................................................. 13
4.7 Marking and sealing .............................................................................................................. 14
4.8 Physical mean to filter the cleaning air ................................................................................. 14
4.9 Safety and security ................................................................................................................ 15
5
Type approval............................................................................................................................ 15
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Annex A PERFORMANCE TESTS
August 2007
16
A.1
General
16
A.2
Breath profile
16
A.3
Test facilities
16
A.4
Accuracy tests
18
A.5
Influence factors in the parameters which characterise the test gases
19
A.6
Physical influence factors
20
A.7
Influence of volume fraction of CO2
23
A.8
Disturbances tests
23
A.9
Physiological influence quantities
27
Annex B Examples of detection of alcohol in upper respiratory tracts
28
B.1 Peak method
28
B.2 Two-measurement cycle
28
B.3 Delay before measurement
30
Annex C General information and breath profile ( informative)
31
Annexe D Test Report Format
37
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Requirements
1
Scope
This International Recommendation applies to quantitative breath alcohol analysers which are
instruments that automatically measure the mass concentration of alcohol in exhaled human breath
representative of the level of alcohol intoxication of the subject.
For the purpose of this recommendation, only ethanol is considered as alcohol.
This Recommendation does not apply to instruments which do not quantitatively indicate the result
of measurement, but which only indicate whether the mass concentration of alcohol exceeds the
allowed limits.
Additionally, national authorities may require that breath alcohol analysers are equipped with
special devices according to the national policy for fighting against alcohol abuse. For example:
•
Device(s) that detects the presence of alcohol in the upper respiratory tracts,
•
prohibition of display or printing of results which do not represent the final measurement
result,
•
making mandatory a printing device,
•
making the measurement impossible in case of no paper is detected in the printing device,
•
requiring additional printed information.
National authorities may require that the breath alcohol analysers convert and display measurement
result obtained in terms of ethanol content in the exhaled human breath either into physiological
conditions or in terms of other quantities. This Recommendation does not cover the metrological
performance of such devices. 1
The purpose of this Recommendation is to specify, the minimum metrological specifications and
tests applicable to type approval, initial verification and in service verification of breath alcohol
analysers, owing to national differences in legal systems.
2
Terminology
2.1
Breath alcohol analyser
An instrument that measures within specified error limits and displays the breath alcohol
mass concentration by analysing exhaled human breath representative of the level of the
alcohol intoxication of the subject.
2.2
Stationary breath alcohol analyser
A breath alcohol analyser intended only for use within buildings or places providing stable
environmental conditions.
2.3
Mobile breath alcohol analyser
A portable breath alcohol analyser intended for use in mobile applications (e.g. in cars).
1
However it is advisable that national penal law defines offences in terms of alcohol in breath so
that these instruments are more appropriately used
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2.4
August 2007
Portable breath alcohol analyser
A breath alcohol analyser which operates with an autonomous battery. It may be used in or
outside buildings or mobile applications.
2.5
Alveolar air
Air contained in the pulmonary alveoli where the gaseous exchange takes place between the
arterial blood and the gas contained within the alveoli.
2.6
End expiratory breath
Air considered sufficiently representative of alveolar air (in opposition to dead anatomical
volume).
2.7
dead anatomical volume
Conducting area of gas flow known as area of conduction without exchange of an average
volume of 150 ml.
2.8
Measuring mode
The clearly indicated mode in which the breath alcohol analyser can make measurements at
the rate normally expected in service and in which it shall meet the performance
requirements of this Recommendation.
2.9
Maintenance mode
The mode in which the breath alcohol analyser can be adjusted and subject to metrological
testing and control.
2.10
Stand by mode
The mode of the breath alcohol analyzer which only certain circuits are energized in order to
conserve power and/or prolong component life, and to attain the measuring mode more
rapidly than would be possible if starting from the un-powered state
2.11
Adjustment device
A device for adjusting the breath alcohol analyser when it is in maintenance mode.
2.12
Fault (OIML D11-3.9)
Difference between the error of indication and the intrinsic error of a measuring instrument.
2.13
Significant fault (OIML D11-3.10)
Fault greater than value specified in this Recommendation.
2.14
Disturbances
An influence quantity having a value outside the specified rated operating conditions of the
measuring system. If the rated operating conditions are not specified for an influence
quantity, it is a disturbance.
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2.15
August 2007
Built-in automatic checking facility
A device which allows verifying, by involving all relevant internal elements, that the breath
alcohol analyser is suitably adjusted. Such a device may include internal checking elements
(for example signal stability, temperature stability) or additional checking external elements
to be connected to the instrument such as optical or electrical filters or cylinder with a known
concentration test gas.
2.16
Drift
The change in the result of a measurement of the same alcohol concentration which occurs
during a stated period of time at a given mass concentration of ethanol in air.
2.17
Memory residual effect
The difference between the results of measurement of the same alcohol concentration when
delivered samples are interposed with a sample containing a specified higher alcohol
concentration.
3
Metrological requirements
3.1
Reliability of the measurement
The breath alcohol analyser shall be designed such that a measurement result is
representative of the alcohol concentration present in the end expiratory breath.
In order to demonstrate the conformity to this requirement the breath alcohol analyser shall
fulfil the requirements in 3.2.3 and the tests in A.5.
3.2
Rated operating conditions
3.2.1
Measuring range
The breath alcohol analyser shall be capable of measuring all mass concentrations in the
range 0.00 mg/L to at least 2.00 mg/L. However, in the measuring mode, the breath alcohol
analyser may indicate 0.00 mg/L for mass concentrations equal to or smaller than a given
value defined under the responsibility of national authorities. Such a masking function shall
be able cancelled in maintenance mode.
The greatest permissible value for the upper limit of the measuring range is 3.00 mg/L.
The breath alcohol analyser shall indicate when its upper limit of measurement is exceeded.
The scale interval is 0.01 mg/L in the measuring mode. Nevertheless, in the maintenance
mode, it shall be possible to display a scale interval equal to 0.001 mg/L.
3.2.2
Physical influence factors
The rated operating conditions corresponding to the physical influence factors are specified
in A.6 for the following performance tests :
•
Dry heat (A.6.1),
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3.2.3
August 2007
•
Cold (A.6.2),
•
Damp heat, steady-state (A.6.3),
•
Random vibrations (A.6.4),
•
Power voltage vibrations (A.6.5),
•
Frequency vibrations (A.6.6),
•
Influence of atmospheric pressure (A.6.7)
Conditions of exhalation
The breath alcohol analyser shall indicate whether the conditions of exhalation (e.g.:
continuity and flow) complied with the conditions specified by the manufacturer in order to
ensure a representative measurement.
These conditions, specified by the manufacturer, shall comply with the following values:
• Exhaled volume : greater than or equal to 1.2 L,
• Pressure : greater than or equal to 10 hPa (new proposition 20 hPa, to be
discussed),
• Flow rate : greater than or equal to 0.10 L/s.
Reference conditions
Ambient temperature
Relative humidity
:
:
23 °C ± 5 °C,
50 % + 30 %,
•
Atmospheric pressure
:
1013 ± 20 hPa,
•
Total fraction by volume of
hydrocarbons (as methane
equivalent) in the environment
:
≤ 2 x 10-6 mol/mol.
3.2.4
•
•
During each test, the temperature and the relative humidity shall not vary by more than 5 °C
and 10 % respectively within the reference range.
3.3
Maximal permissible errors (MPE)
The following MPE shall apply within the rated operating conditions (specified in 3.2).
3.3.1
Maximum permissible errors for type approval and initial verification
The maximum permissible errors, positive or negative, on each individual
indication are :
+ 0.020 mg/L or + 5 % of the true value of mass concentration, whichever the
greater, for all mass concentrations over the measuring range;
3.3.2
Maximum permissible errors for breath alcohol analysers in service (for the
subsequent verifications)
+ 8 % of the true value of mass concentration or + x mg/L, whichever the greater,
for all mass concentrations over the measuring range.
x is a fixed value which is defined by National Authorities and which shall not be
less than 0.02 mg/L
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3.4
August 2007
Disturbances and other influence quantities
3.4.1
Disturbances
In the presence of a disturbance, the breath alcohol analyser shall display no
significant fault.
The significant fault is equal to the magnitude of the maximum permissible error
applicable to type evaluation for the following disturbances :
•
Radiated radiofrequency, electromagnetic fields (A.8.1),
•
Conducted radiofrequency fields (A.8.2),
•
Electrostatic discharges (A.8.3),
•
Bursts on supply lines (A.8.4),
•
Bursts on signal, data and control lines (A.8.5),
•
Surges on signal, data and control lines (A.8.6),
•
AC mains voltage dips short interruptions and voltage variation (A.8.7),
•
Electrical transient conduction for external batteries of a vehicle (A.8.8),
•
Mechanical shocks (A.8.9),
•
Shakes (A.8.10),
•
Damp heat cyclic (A.8.11),
•
Storage (A.8.12).
The corresponding tests are described in the Annex A.8
3.4.2
Other influence quantities
3.4.2.1
Physiological influence quantities
The corresponding test and acceptance criteria are specified in A.9 (interfering
substances) and A.7 (volumetric fraction of CO2)
3.4.2.2
Influence of substance in ambient air
The instrument shall not exceed the MPEs in the presence of hydrocarbons in the
ambient air corresponding to a total fraction by volume of hydrocarbons (as
methane equivalent) equal to 5 ppm.
3.5
Estimation of the repeatability
3.5.1
Experimental standard-deviation
The experimental standard-deviation is given by the formula :
n
∑ (Y
i
s=
i =1
−
− Y )2
n −1
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August 2007
where :
n = the number of measurements made at a given mass concentration ;
Yi = the ith measurement (out of n) for the given mass concentration ;
−
Y = the arithmetic mean of the n values.
Requirement applicable to the type approval and the initial verification
3.5.2
The experimental standard deviation for all mass concentrations shall be less or
equal to one third of the maximum permissible error.
3.6
Drift
3.6.1
Zero drift
The drift from 0.00 mg/L shall be less than 0.010 mg/L in 4 hours under reference
conditions as defined in Annex A.4.
3.6.2
3.7
Drift at 0.40 mg/L
3.6.2.1
Short-term drift: the drift at 0.40 mg/L shall be less than 0.010 mg/L in 4 hours
under reference conditions as defined in Annex A.4.
3.6.2.2
Long-term drift: the drift at 0.40 mg/L shall be less than 0.020 mg/L in two
months under reference conditions as defined in Annex A.4.
Memory and residual effect
3.7.1
Memory effect
The memory effect shall be less than 0.010 mg/l when the test is conducted
according to A.4.3.1.
3.7.2
Small changes in mass concentration
The error in the result obtained with a gas having a mass concentration which is
0.10 mg/L less than that of another gas previously injected shall be less than or
equal to the maximum permissible error for the lower mass concentration.
3.8
Durability
All the tests specified in this recommendation shall be performed on the same instrument in
order to demonstrate the durability of the instrument.
4
Technical requirements
4.1
Physical quantity and unit of measurement
The breath alcohol analyser shall display measurement results in term of mass concentration
of alcohol in a specified volume of exhaled air.
The mass concentration shall be indicated in milligram per litre of exhaled breath (mg/L).
The national authorities may require to use an equivalent unit of measurement if the
indication is in conformity with the legal international units and as long as it represent a
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August 2007
mass concentration of alcohol in a specified volume of exhaled air. The reference conditions
for all measurement alcohol concentration including calibration are :
Temperature : 34.0 °C,
Pressure : Patm during the tests (hPa)
Humidity : 95 % HR (in the pressure condition during the breath) ,
Presence of CO2 : 5 %.
4.2
Display
The result of measurement shall be displayed digitally by means of aligned figures. The
display in the measuring mode shall consist of the display in metrological testing mode
rounded down to 0.01 mg/L (e.g. a measured value of 0.427 mg/L shall be displayed as 0.42
mg/L).
The height of the figures on the display shall be equal to at least :
5 mm for illuminated displays,
10 mm in all other cases.
The name of the unit of measurement or its symbol shall appear in close proximity to the
measurement indication. The characters used shall be at least 3 mm high.
If the characters are not illuminated, the display shall have an illumination device.
4.3
Printing device
The breath alcohol analyser may be equipped with a printing device which print at least :
•
the result of the measurement,
•
the symbol of the unit in which the result is expressed.
If the printing device is in the scope of the type approval, the printing device shall operate
during the influence factors and disturbances.
The printed result shall not differ from the indicated one displayed by the indicating device.
If the symbol of the unit is pre-printed, the paper shall be especially prepared for the printing
device.
Printouts shall remain readable for at least thirty days, even when exposed to daylight or
equivalent lighting.
The manufacturer shall recommend a paper type.
The printing device shall be equipped with an automatic checking facility to verify the
correct transmission of the data from the breath alcohol analyser to the printing device. At
least the following shall be checked :
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•
•
August 2007
presence of paper;
the electronic control circuits.
When the printing device is not included into the measuring instrument, the National
Authorities shall defined the requirements to prevent intentional and accidental modification
of the data during their transmission.
4.4
Measuring conditions
At least before each measurement, the instrument shall automatically adjust or check
adjustment implementing the built-in automatic checking facility. The instrument shall
indicate a zero with a tolerance ± 0.005 mg/L, using an appropriate purge. When this
adjustment is not possible or this check gives negative results, the instrument shall indicate
an alarm and shall not allow any further measurement.
The breath alcohol analyser shall indicate its readiness to start a measurement and shall not
perform measurements when it is not ready. When after a period of time the instrument is no
longer ready to perform measurements, it shall indicate this.
The breath alcohol analyser shall monitor the continuity of exhalation and shall give an
indication if the flow of exhaled air is interrupted between the beginning and the end of the
sampling. A signal (preferably audible) shall indicate the continuity of the exhalation.
When a measurement result is nil, it shall not be possible to confuse such a result with the
zero indication prior to measurement.
The breath alcohol analyser shall be equipped with a function which automatically detects
whether the measuring result is affected by the presence of alcohol in the upper respiratory
tracts. Examples of compliance are given in Annex B.
The user shall not have access to the maintenance mode nor to the adjustment device.
4.5
Checking operations
When powered on, the instruments shall automatically check their correct operation (e.g.:
checksums, watchdogs, etc.). When any defect or an error signal is detected, the instrument
shall indicate an alarm and shall not allow any further measurement.
EBA’s shall check correct operation automatically both before each measurement and after
any measurement which gives a result greater than a predetermined value of the mass
concentration (this value may be zero)
4.6
Suitability for use
4.6.1
Warm-up time
Under reference conditions (3.2.3), the breath alcohol analyser shall be capable of attaining
the measuring mode :
• 15 minutes after being switched on,
• 5 minutes after switching from stand-by mode to measuring mode.
However if these requirements are not fulfilled, the corresponding times shall be marked on
the breath alcohol analyser and provided in the user manual
4.6.2
Availability for measurement
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After successful checking operation (including automatic checking of adjustment), using the
built-in automatic checking facility, from the moment the breath alcohol analyser indicates
that it is ready to receive an exhalation, the breath alcohol analyser shall be available at least
one minute.
After a period time not using the instrument, it is no longer ready to perform a measurement
and it shall indicate that.
4.6.3
Availability of the measurement result
It shall be possible to retain the results in a readable or accessible form for at least 15
minutes.
If other measurements can be performed during the period, , the previous result shall be
accessible without ambiguity.
If this requirement can be met only by printing the results, the absence of paper in the
printer shall prevent measurement being made.
4.7
Marking and sealing
The breath alcohol analyser shall be marked with a tamper evident label on a visible part of
the instrument with the following information:
•
type approval mark
•
manufacturer's name
•
denomination of the instrument
•
serial number
•
measurement range
•
stationary, mobile or portable
•
ambient conditions
•
power supply range
Appropriate seals shall protect the integrity of the instruments.
4.8
Physical mean to filter the cleaning air
It shall be possible to change this mean without removing any sealing device, if the filter is a
particle filter.
For any another type of filter, the manufacturer shall define the periodicity of this
replacement. The replacement is considered as repairing operation.
To replace this filter, it shall be necessary to break the sealing device
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4.9
August 2007
Safety and security
The EBA shall be capable of being used under satisfactory hygienic conditions. It shall be
possible to change the mouthpiece for each measurement; mouthpieces shall be individually
packaged.
EBA’s shall conform to relevant national regulations and standards for electrical safety and,
where appropriate, for compressed gases. Verification of compliance with these regulations and
standards is not within the scope of this Recommendation.
The EBA breath sampling system including the mouthpiece shall not allow the subject of the
measurement to inhale contaminated air from previous usages. It shall prevent the deposition of
droplets from exhaled breath in the EBA.
5
Type approval
Manufacturers shall provide the technical documentation, a user manual for the breath alcohol
analyser and the description of the adjustment procedure. Other information may be provided such
as information on performance tests, on calibrations that support a determination whether the
design of the breath alcohol analyser meets the requirements of this Recommendation.
The technical documentation shall include:
•
a list of the electronic sub-assemblies with their essential characteristics
•
a description of the electronic devices with drawings, diagrams
•
a description of the software and its characteristics(including identification numbers) and
operation including a list of the data variables and the circumstances when they may be
changed
•
mechanical drawings
•
a plan for marking and sealing .
If the breath alcohol analyser is equipped with a printing device, the manufacturer shall provide
information about the quality of the printing paper to fulfil the requirements of readability
defined in 4.4.
Type evaluation consists in assessing the compliance of the breath alcohol analyser with each
requirement of this Recommendation.
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Annex A
PERFORMANCE TESTS
Mandatory
A.1
General
This annex defines the program of performance tests intended to verify that the breath alcohol analyser
operates as intended in a specified environment and under specified conditions. Each test indicates,
where appropriate the reference conditions for determining the intrinsic error.
Different kinds of tests apply :
•
Test to ensure representative sampling,
•
Accuracy tests (including repeatability, drift and memory and residual effect),
•
Influence factors,
•
Disturbance tests.
The tests specified in this Recommendation constitute minimum test procedures. Further tests may be
undertaken, if necessary, in order to clarify issues of compliance of the breath alcohol analyser with
the requirements of this document.
A.2
Breath profile
The human breath containing alcohol may be considered corresponding to the following
characteristics :
•
Evolution of the alcohol concentration during the breath
The evolution of the breath of a human being is characterized by a plateau in the curve of mass
concentration against time during the last part of the exhalation. The mass concentration at this
plateau represents the mass concentration in the end-expiratory breath.
Annex C2 shows the general form of this breath profile.
•
Evolution of the flow rate curve during the breath
Annex C1 shows the general form of this breath profile.
A.3
Test facilities
The apparatus shall be able to determine the true value of the mass concentration with an
uncertainty less than or equal to one third of the maximum permissible error (for example
expressed at a level of confidence of about 95 % calculated with k = 2). This uncertainty
includes the components of uncertainty on the determination of the plateau.
Taking into account of the testing apparatus, the tests shall be conducted with the maximum
frequency allowed by the breath alcohol analyser.
The breath alcohol analyser may be completely calibrated, if necessary, by the manufacturer
before type approval testing begins. Thereafter no adjustment shall be carried out until all type
approval testing is complete.
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A.3.1
August 2007
Characteristic reference values of the test gas
Unless otherwise specified, the test gas injected continuously into the breath alcohol
analyser shall be characterised by the following parametric values :
• Delivered volume : 2 L + 0.3 L,
• Total duration of injection (into breath analyser) : 5 s + 0.5 s,
• Type of profile : constant flow rate,
• Relative humidity of the gas : at least 90 % at the exit way pressure of the instrument
• Gas temperature : 34 °C + 0.5 °C,
• carrier gas : air containing insignificant concentrations of relevant impurities with
volumetric fraction of CO2 : 5 % + 1 %.
The completed test reports shall indicate what kind of test means has been used for each test.
Test reports shall indicate when other gases were used and how their equivalence with the
reference gases was established.
Simplified means
This Recommendation permits the use of calibration gases produced by simplified means for
some tests. Such means may consist in the use of dry gases or wet gases generated by simple
test means (e.g. the absence of CO2 in test gases, constant mass concentration during
injection). The completed test reports shall indicate when such alternative tests have been
implemented.
For tests other than those for accuracy and to demonstrate the capability of the breath
alcohol analyser to make measurements on the end expiratory air, the following simplified
means could be used :
•
Dry gases, which can be used for tests defined in A.6.4, A.6.5, A.6.6, A.8.1 to A.8.10
(included),
•
Gases without CO2, which can be used for tests defined in A.6, A.8.
In all cases, the evolution of the concentration and the flow rate during injection may be
constant.
For cases involving dry gases in cylinders:
• variations of atmospheric pressure and variation of the compressibility factor between
filling and usage conditions must be taken into account,
• the quality of the, gas regulators and the manner by which it is delivered to the breath
alcohol analyser, should be taken into account to minimize contamination and a change
in the composition of ethanol throughout its use cycle.
• test facilities must be taken into account in calculations of the uncertainties of the
measurement
A.3.2
Demonstration of the capability of the breath alcohol analyser to make measurements of end
expiratory breath
In order to demonstrate the capability of the breath alcohol analyser to make measurements
on the end expiratory breath , the apparatus used by the laboratory shall permit be capable of
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August 2007
performing tests defined in Annex A.6, corresponding to the breath profile describe to Annex
A.2.
A.3.3
Accuracy tests
The apparatus shall be of one of the two following types :
Type 1 : the apparatus delivers constant concentration curves ;
Type 2 : the apparatus is similar to the one corresponding to A.3.1. During tests, the plateau
shall be reached when half of the test volume has been injected ( ± 10 % of total volume).
A.4
A.4.1
Accuracy tests
Maximum permissible errors and repeatability
Compliance with maximum permissible errors requirement defined in 3.3.1 and repeatability
requirement defined in 3.5 shall be verified at least at the following nominal values:
Test gas n°
Mass concentration (mg/L)
1
0.00 to 0.05
2
0.10
3
0.25
4
0.40
5
0.70
6
0.95
7
1.50
8
2.00 mg/L or the upper value
specified by the manufacturer
For type approval, at least 20 measurements shall be made consecutively at each gas
concentration.
For each test gas, each of the 20 measurement results shall comply with the maximum
permissible error requirement.
A.4.2
Drift
The compliance with the drift requirements shall be tested at certain gas concentrations.
Zero drift: Test gas n° 1,
Drift at 0,4 mg/ L: test gas n° 4,
Test procedure for each test gas:
- 10 subsequent measurements
- after the time interval specified under 3.6 again 10 subsequent measurements
For each drift test, the deviation between the mean value of the two series of measurements
shall fulfil the requirements for drift (3.6.)
Other tests for type approval may be performed during the drift tests.
A.4.3
Memory and residual effect
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A.4.3.1 Memory effect
The breath alcohol analyser shall be subjected to an initial test that includes 10
measurements using test gas n° 2. The mean value of these 10 measurements is
calculated.
Then, the breath alcohol analyser shall be subjected 10 times to the following
cycle :
• one measurement using test gas n° 7 or n°8, which ever greater,
•
one measurement using test gas n°2.
The mean value of these 10 measurements with test gas n° 2 during the cycle is
calculated.
For the mass concentration at 0.10 mg/L, the difference between the two calculated
mean values shall be less than the limit specified in 3.7.1.
A.4.3.2 Small changes in mass concentration
The breath alcohol analyser shall be subjected to 10 measurements using test gas
n° 4. The mean value of these 10 measurements is calculated.
Then the breath alcohol analyser is subjected to 10 measurements using test gas
n° 3. The mean value of these 10 measurements is calculated.
The difference between these two mean values shall comply with the requirement
specified in 3.7.2.
A.5
Influence factors in the parameters which characterise the test gases
These tests shall be carried out under a breath profile as defined in A.2.
For these tests, the values of the parameters that are not specified shall be those defined in
the introduction of A.3. The values of the parameters to be varied are specified in A.5.1 to A.5.4.
For each test, 10 measurements using test gas n° 4 shall be performed. Each of these 10
measurements shall fulfil the maximum permissible error requirement defined in 3.3.1.
To be representative of the human exhalation variation, it is necessary to make vary two
parameters in the same time (volume, duration and flow rate are correlated)
A.5.1
Influence of delivered volume (in conjunction with exhalation time)
•
•
A.5.2
First test :
•
delivered volume : 1.2 L + 0.1 L,
•
duration of injection: 4 s + 0.5 s.
Second test :
•
delivered volume : 4.5 L + 0.3 L,
•
duration of injection: 15 s + 0.5 s.
Influence of the duration of exhalation (in conjunction with flow)
• First test:
•
delivered volume: 2.5 L + 0.2 L,
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•
A.5.3
• duration of injection: 5 s + 0.5 s.
Second test:
•
delivered volume: 2.5 L + 0.2 L,
•
duration of injection: 15 s + 0.5 s.
Influence of the breath profile
• First test:
•
A.5.4
August 2007
•
delivered volume: 3 L + 0.2 L,
•
duration of injection: 5 s + 0.5 s,
•
type of profile : constant flow rate.
Second test:
•
delivered volume: 3 L + 0.2 L,
•
duration of injection: 5 s + 0.5 s,
•
type of profile : forceful expiry (according to annex C1).
Influence of the flow rate (in conjunction with volume)
• First test :
• Delivered volume : 1.5 L ± 0.1 L,
• Duration of injection : 5 s ± 0.5 s.
•
Second test :
• Delivered volume : 4 L ± 0.2 L,
• Duration of injection : 5 s ± 0.5 s.
A.5.5
Influence of interruption in the breath flow
• First test : the injection of gas normally required for the reference conditions specified in
A.3 shall be stopped 1 + 0.5 s after the start of injection.
• Second test : the injection of gas normally required for at least 15 s (see A.5.2) shall be
stopped at 6 + 1 s after the start of injection.
• Third test : short flow interruption. The injection of gas supplied at a flowrate equal to
0.15 L/s is decreased at a flow rate equal to 0.03 L/s.
For these 3 tests, the instrument shall not give a result.
A.6
Physical influence factors
The effect of each influence factor shall be determined separately and influence factors not under
investigation shall remain at their reference values as specified in A.4.
The tests shall be carried out using test gas n° 4. At least 5 measurements shall be performed in each
test condition.
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For each test condition and each measurement, the maximum permissible error requirement specified
in 3.3.1 shall be fulfilled. Nevertheless, in the test at the extreme value of hydrocarbons in the
environment, it is acceptable that the breath alcohol analyser gives no result.
A.6.1
Dry heat (See OIML D 11, 10.1.1)
The tests consists of exposure of the breath analyser to a temperature defined below
according to type of breath alcohol analyser under “free air” conditions for a two hours
period after the breath alcohol analyser reached temperature stability.
Temperature
Stationary
Mobile
30 °C
40 °C
Duration
2 hours
Number of cycle
1
Portable
40 °C or 50 °C *
*Specified by the State
A.6.2
Cold (See OIML D 11-10.1.2)
The tests consists of exposure of the breath analyser to a temperature defined below
according to type of breath alcohol analyser under “free air” conditions for a two hours
period after the breath alcohol analyser reached temperature stability.
Stationary
Mobile
Portable
Temperature
5 °C
- 10 °C
Duration
2 hours
Number of cycle
1
-25 °C or -10 °C *
* Specified by the State
A.6.3
Damp heat, steady-state (non condensing) (See OIML D 11-10.2.1)
The tests consists of exposure of the breath alcohol analyser to the specified high level of
temperature and the specified constant relative humidity during the time defined below
according to the severity level.
The error of the breath alcohol analyser is determined one time per day and at the end of the
test after a recovery period of one hour.
A.6.4
Mobile
Portable
Temperature
30 °C
40 °C
Humidity
85 % rel
93 % rel
Duration
2 days
4 days
Random vibrations (See OIML D 11-11.1.1)
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This test is applicable to mobile and handheld breath alcohol analysers. During the test, the
breath alcohol analyser is powered off. The test consists of exposure to the vibration level
hereafter defined:
•
Total frequency range : 10 Hz to 150 Hz
•
Total RMS level : 7 m.s-2
•
ASD level 10 Hz- 20 Hz : 1 m2.s-3
•
ASD level 20 Hz- 150 Hz : - 3 dB/octave
The breath alcohol analyser shall, in turn, be tested in three mutually perpendicular axes
mounted on a rigid fixture by its normal mounting means so that the gravitational force actes
in the same direction as it would be in normal use.
The duration of the test shall be a minimum of two minutes per axis.
The error of the breath alcohol analyser is determined after the whole test has been carried
out.
A.6.5
Power voltage variations (See OIML D 11-13.1, 13.2)
The error of the breath alcohol analyser is determined in the following conditions:
•
when the instrument is powered on at the upper limit of the voltage, if applicable,
•
when the instrument is powered on at the lower limit of the voltage.
Stationary
Stationary
Stationary or
(AC mains voltage)
(DC mains voltage)
portable or mobile
(internal battery)
Upper limit
Nominal voltage + 10%
Defined by the
manufacturer
N/A
Lower limit
Nominal voltage – 15 %
Defined by the
manufacturer
Limit where the
instrument ceases to
operate within the
MPE
For breath alcohol analysers powered from external 12 V road vehicle batteries, the upper
and lower limits are defined hereafter:
•
Upper limit: 16 V
•
Lower limit: limit where the instrument ceases to operate within the MPE.
A.6.6
AC mains frequency variations (See OIML D 11-11.3)
This test is applicable to stationary breath alcohol analysers powered by AC mains voltage
(direct or through a generator).
Upper limit
Nominal frequency + 2 %
Lower limit
Nominal frequency – 2 %
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A.6.7
August 2007
Influence of atmospheric pressure (see OIML D11-10.4)
• First test:
•
Atmospheric pressure: 860 hPa + 10 hPa
Second test:
Atmospheric pressure: 1060 hPa + 10 hPa
A.7
Influence of volume fraction of CO2
•
A.8
Mass concentration by volume of CO2: 10 % + 1 %
Disturbances tests
The tests shall be carried out using test gas n° 4. At least 5 measurements shall be performed in each
test condition except for the chapter A.8.1, A.8.2., A.8.8 in witch, the measurements shall be made
during all the disturbances test s.
For each disturbance test unless otherwise specified, the difference between the result of the test and
the performance at reference conditions shall not exceed the significant fault value specified in 3.4.1,
It is acceptable that the breath alcohol analyser gives no result during the disturbance testing.
The error of the instrument is generally determined during the disturbance except for mechanical
shocks (A.8.9.), shakes (A.8.10) and storage test (A.8.12).
When several test configurations are specified for one disturbance test, the fault shall be determined
for each of these configurations.
The application of each test shall be long enough to apply during a complete cycle of measurement of
the breath alcohol analyser.
For the tests specified in A.8.1 to A.8.3, conventionally 3 cycles of tests are performed starting each
test at different moment of the measuring cycle.
A.8.1
Radiated, radio frequency, electromagnetic fields (See OIML D 11-12.1.1)
The breath alcohol analyser
hereafter:
•
Frequency range:
•
Modulation:
•
Field strength:
shall be exposed to electromagnetic field strength as specified
from 80 MHz to 2000 MHz
80 %AM, 1 kHz, sine wave
10 V/m
This test includes the susceptibility to electromagnetic fields of general origin and to those
specifically caused by digital radio telephones.
In the event that the breath alcohol analyser has no mains or input ports, the applicable
frequency range is from 26 MHz to 2000 MHz.
The frequencies are stepped across incrementally with the step size not exceeding 1% of the
previous frequency.
A.8.2
Conducted radio-frequency fields (See OIML D 11-12.1.2)
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This test doesn’t apply if the breath alcohol analyser has no mains or other input ports.
Otherwise it shall be conducted on supply lines and on all connection cables if the instrument
is composed of several elements connected together. For connection cables, the test shall be
performed at each extremity of the cables if both of the elements are part of the instrument.
The test conditions are the following:
•
Frequency range:
from 0,15 MHz to 26 MHz
•
Modulation:
80 %AM, 1 kHz, sine wave
•
A.8.3
RF amplitude (50 Ω): 10 V
Electrostatic discharges (See OIML D 11-12.2)
Contact discharges are the preferred test method. Nevertheless, air discharges shall be used
where contact discharges cannot be applied (e.g. non conductive surfaces).
Both types of application shall be performed:
•
Direct application
•
Indirect application
The discharges shall be applied on each surface accessible in normal operation. 5
measurements shall be performed in each surface.
At least ten successive discharges shall be applied with a time interval between discharges of
at least ten seconds on each point of application. The number of points of application on each
surface will depend on the size of the instrument and shall be specified in the test report.
The test conditions are the following:
•
Test voltage for contact discharge:
•
Test voltage for air discharge:
A.8.4
6 kV,
8 kV.
Bursts on supply lines (See OIML D 11-13.5)
This test is only applicable to breath alcohol analyser powered from AC mains or DC mains.
The test consists of exposure to bursts of voltage spikes of 1 kV. Each spike shall have a rise
time of 5 ns and a half amplitude duration of 50 ns. The burst length shall be 15 ms and the
burst period (repetition time interval) shall be 300 ms.
At least ten positive and ten negative bursts randomly phased shall be applied.
A.8.5
Bursts on signal, data and control lines (See OIML D 11-12.4)
Both positive and negative polarity of the bursts shall be applied.
A.8.6
Amplitude (peak value)
1 kV
Repetition rate
5 kHz
Surges on signal, data and control lines (See OIML D 11-12.5)
At least 3 positive and 3 negative surges shall be applied. The injection network depends on
the lines the surge is coupled into:
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Unbalanced lines
Balanced lines
A.8.7
Line to line
1 kV
Line to earth
2 kV
Line to earth
2 kV
AC mains voltage dips, short interruptions and voltage variations (See OIML D 11, 13.4)
The mains voltage reductions shall be repeated 10 times with an interval of at least
10 seconds.
The test conditions are the following:
Test a
Test b
Test c
Reduction
100 %
100 %
30 %
Duration
0.5 cycle
1 cycle
25 cycles
The error of the breath alcohol analyser is determined for each configuration of testing.
For voltage interruption, the test conditions are the following:
•
•
A.8.8
Interruption:
Duration:
> 95 %
250 cycles
Electrical transient conduction for external batteries of a vehicle (See OIML D 11, 14.2.2)
This test shall be applied to breath alcohol analyser powered from external 12 V road vehicle
batteries. If the nominal value for the breath alcohol analyser is 24 V, the tests should be
done as stated for 24 V in accordance with OIML D11, 14.2.2.
The test conditions are the following:
Test pulse 1
A.8.9
Level
- 100 V
Minimum
number of
pulses or test
time
5000 pulses
Test pulse 2
Test pulse 3
2a
3a
+ 50 V
2b
3b
+ 10 V - 150 V + 100 V
5000 pulses
1 hour
Test pulse 4
-7V
1 pulse
Mechanical shocks (See OIML D 11-11.2)
• For stationary or/and mobile breath alcohol analyser :
The breath alcohol analyser is placed on a rigid surface in the position in which it is
normally used, is tilted on one bottom edge and is then allowed to fall freely onto the
test surface. This test shall be repeated for each edge in turn (subject to a maximum
inclination of 30 °).
•
The height of fall given below is that of the opposite edge.
For handheld breath alcohol analyser :
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3 arbitrary positions are chosen.
A.8.10
Stationary
Mobile
Portable
Height of fall
25 mm
50 mm
1m
Number of fall
1
1
3
Shakes
This test simulates shocks in a car trunk. The breath alcohol analyser is placed in its
reference position on a table which can generate shakes in the following conditions:
•
wave shape:
half-sinusoid
•
amplitude:
10 g (g = 9.81 m/s2)
•
duration:
6 ms
•
frequency:
2 Hz
•
number of axes:
3 perpendicular axes
•
number of shakes:
1000 for each axes
A.8.11
Damp heat cyclic (condensing) (OIML D 11, 10.2.2)
The breath alcohol analyser shall be exposed to cyclic variation between 25 °C and the
temperature specified below. The relative humidity shall be above 95 % during the
temperature change and low temperature phases and at 93 % at the upper temperature
phases.
Condensation should occur on the breath alcohol analyser during the temperature rise.
The 24 cycle consists of :
1) Temperature rise during 3 h,
2) Temperature maintained at the upper value during 9 h,
3) Temperature lowered to the lower value during 3 h,
4) Temperature maintained at the lower value during 9 h.
A.8.12
Mobile
Portable
Temperature
55 °C
55 °C
Duration
2 cycles
4 cycles
Storage test
The error of the breath alcohol Analyser is determined in reference condition prior to the
test.
Then, the breath alcohol analyser is powered off and exposed to a low temperature of - 25 °C
during six hours and to a high temperature of 70 °C during six hours.
The change of temperature shall not exceed 1 °C/min during cooling down and heating up.
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After a recovery period of one hour, the error of the breath alcohol analyser is determined
and the default is calculated.
A.9
Physiological influence quantities
The breath alcohol analyser shall be tested according to the following procedure :
•
determination of the indication for a dry test gas having an ethanol content of 0.4 mg/L
+ 5 % without any interfering substance.
•
determination of the indication for the same test gas with one and only one of the
interfering substances listed in the following table at the indicated mass concentration :
Interfering substance
Nominal value for vapour mass concentration mg/L (+ 5 %)
Acetone
0.5
Acetaldehyde
0.15
Methanol
0.1
Isopropanol
0.1
Carbon monoxide
0.2
Toluene
0.2
If the variation of the indication is not more than the maximum value defined in …(0,1 mg/L for the
current interfering substances in the above table) the breath alcohol analyser has passed the test for the
interfering substance concerned. If the variation is more than the value defined in … and if no error
message is given, the breath alcohol analyser has failed. If an error message is given, another test shall
be performed with the same interfering substance at a mass concentration 5 times smaller. In that case
the variation shall not be more than a fifth of the maximum value defined in ….
This test shall be performed at least 5 times for each of the interfering substance. Each time, the
requirement shall be fulfilled.
National responsible bodies may decide to test the influence of other compounds.
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Annex B
Examples of detection of alcohol
in upper respiratory tracts
(informative)
The member State may choose one, two or all the following solutions for detection of alcohol in the
upper respiratory tracts (B1 or B2) or avoiding the corresponding influence (B3).
B.1
Peak method
In the event that the breath alcohol analyser mouth alcohol detection operates by the detection of a
peak in the IR signal ,, the following test, allows demonstrating that the instrument is able to detect
alcohol in upper respiratory tracts.
The test consists in injecting a test gas providing an evolution of the mass concentration as
indicated below:
The characteristics of the gas injected are the following:
•
delivered volume:
3 L ± 0.2 L,
•
duration:
15 s ± 0.5 s
•
mass concentration at maximum of the curve:
0.4 mg/L ± 0.020 mg/L
Ten measurements shall be performed and the instrument shall detect the presence of alcohol in the
upper respiratory tracts and shall deliver no measurement result.
B.2
B.2.1
Two-measurement cycle
First method
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The measuring cycle shall include two measurements. These two measurements shall be performed
within a delay no smaller than 2 min.
The breath alcohol analyser shall be able to memorize that constitute the offence of driving or
working under influence of alcohol hereafter called “the legal value”.
The measuring cycle can be stopped after the first measurement if the concentration value is less
than the legal value. In that case, the result of measurement shall be displayed and printed, if
applicable.
If one of the two measurements is less than the legal value and the other one more than or equal to
the legal value, the smallest result shall be displayed and printed (if applicable). There is no need of
a comparison between the two results.
If both of the two measurements are more than or equal to the legal value, it is necessary to
calculate the ratio :
R = 1−
C2
/ t , where t is the time difference between the end of the first breath and the end of the
C1
second breath.
If R is less than 0.03 min-1, the member State may choose one of the two following solutions:
•
the smallest value of C1 and C2 is displayed and printed (if applicable).
•
the two values C1 and C2 are displayed and printed (if applicable).
In any case, when the second measurement is not performed, it is possible to indicate the unique
available result as an indicative one for instance indicating “measuring cycle not completed”.
If R is more than or equal to 0.03 min-1, the measuring cycle shall be cancelled and the breath
alcohol analyser shall display a warning message to specify that the cycle is not valid and that a
new one shall start.
B.2.2
Second method
The breath analyser shall use a measuring cycle involving two subject sample measurements, each
measurement corresponding to an exhalation. The two subject sample measurements are separated by
at least 2 minutes. The resultant displayed or recorded measurement in a subject test is to be specified
by the legal authority (e.g. lower value, mean of the two values or both values).
If the difference between the two subject sample measurements exceeds the greater of the following
two values:
• 0.10 mg/L, or;
• 20% relative of the smallest of the two measurements;
Note: the national authority may elect to test to breath differences that are tighter than those listed
above. The national authority may also elect to not perform a comparison of samples in the event that
either of the sample measurements are below the alcohol level that constitutes the offence of driving or
working under influence of alcohol.
Then the analyser shall automatically invalidate the measurement cycle because of breath difference,
based on national requirements.
The test procedure for this function consists of measuring two samples of test gases differing by
12.5%, in a measurement cycle consisting of two measurements separated by at least two minutes, but
no longer that 5 minutes. The characteristics of the test gases are:
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• First test gas: Test gas No. 4
• Second test gas: Test gas No. 3
• Duration of injection: 5 s
• Duration of plateau:= 3 s
• Volume: 3 L
The mass concentration at maximum of an injection curve is 0.40 and .25 mg/L, respectively, with
the second gas being lower than the first test gas. The results of the sequential test shall be that the
instrument will either invalidate the measurement cycle and/or display a warning as required by the
national authority
B.3
Delay before measurement
An alternative solution is to ensure that sufficient time has elapsed since the consumption of alcohol to
ensure that it has been cleared from the upper respiratory tract. A delay of 15 min is a reasonable limit
if combined with an other method (as defined in A1 or A2).
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Annex C
General information and breath profile ( informative)
(explanatory Note)
The study of the human behaviour in front to a control of blood alcohol content and its physiology
shows a great diversity on the manner and the capacity of an individual to carry out a breath
(voluntarily or not) in a EBA.
If it is easy to take into account and to fix the following factors of influences: volume, time of expiry;
it is more complicated to rule on problems of flows and determination of plate of alcohol
concentration.
Indeed, it is obvious that the variation of the flow of expiry (of the pressure) at the time of a breath
will be very different while realizing:
a long and regular breath (flow at the time of the constant breath or presenting a very light decrease)
a dynamic and short breath (peak of the flow at the beginning of the breath and fast decrease at the end
of the breath)
Knowing that the instruments can be influenced by variations of pressure at the time of a breath; it is
important to consider this new factor of influence.
Same manner, the taking into account of different the volume died from the physiological point of
view from the individuals highlight a dilution of the alcohol concentration contained in the air cells
(representative of the alcohol concentration contained in blood) and the volume of the high respiratory
tracts (free from alcohol or more precisely if one considers a presence of alcohol on the mucous
membranes that Ci no representative of alcohol is contained in the air cells)
Present the appendix aims at:
to present using theoretical curves the physical phenomena allowing to characterize the influence
factors–
to prepare the next ones discussed in order to rule on the types of profiles and the criteria of
acceptances
C.1
MEASUREMENT FLOW RATE DURING EXHALATION
The object of this chapter is to define a method making it possible to fix characteristics for the
determination of the variation of the air flow at the time of an expiry.
This chapter relates to mainly the test facilities and relates to the definitions of the breaths of tests
Curves of the flow rate as a function of volume obtained from a human exhalation
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Conventional curve of forced exhalation:
The curve is divided into two distinct areas: ·
• the first part of the curve (located in the first ¼ of the time of exhalation) represents the peak of
flow at the time of the exhalation
• the second part represents a regular decrease of the flow of breath
recording curve of flow rate during a forceful expiry during an humain breath through an EBA
flow rate as a fonction of time
45
40
flow rate (L/min)
35
30
25
20
15
10
5
0
0
1
2
3
4
5
6
7
8
9
time of exhalation (s)
Standard to be respected: ·
• during the first ¼ of the time of exhalation, the maximum flow rate is reached.
• at to the 2/3 of the time of exhalation, the flow rate of breath must be lower than the 2/3 of the
maximum flow rate.
• starting from the maximum flow rate, the flow rate shall significantly decrease without
interruption of breath.
note: this standard is sufficiently flexible to allow an easy simulation of a forced exhalation
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C.2 MEASUREMENT ALCOHOL DURING EXHALATION / DETERMINATION OF THE
ALCOHOL PLATEAU
The duration of the plate of the alcohol concentration in a human breath shows very variable
characteristics according to the morphology of the subjects.
It is an important influence factor for the determination of the alcohol concentration
The object of this chapter is to define a method making it possible to fix characteristics for the
determination of over the duration of the alcohol plate at the time of an expiry.
This chapter relates to mainly the test facilities and relates to the definitions of the breaths of tests
Curves of the alcohol concentration as a function of time obtained from a human exhalation
Theoretical curves:
By considering an average dead anatomical volume of 150 ml, a theoretical curve of the alcohol
concentration (expressed in %) according to time and volume of the breath can be calculated starting
from the following formula:
⎡ D * (100 − C ( i −1) ) * (t i − t ( i −1) ) ⎤
C i = C ( i −1) + ⎢
⎥
Vm
⎣
⎦
(C 0 = 0) ; i = incremental indice
where C = alcohol concentration (expressed in %)
D = flow rate (L/s)
t = time of exhalation (s)
Vm = dead anatomical volume (L)
note : this is a reference to the volume of air from the upper respiratory tract
In theory, the alcohol concentration representative of alveolar air is obtained in the last third of the
time of expiry (concentration superior to 99 % of the maximum value).
This value (99 % of the waiting concentration) is a proposition based on the statistic rules about
response time. Another value can be proposed for example 99.5.
This value and its variations must be taken into account in the global calculation of the overall
uncertainty of the test facility in accordance with the requirement of chapter A.3. (Note: 1/3 EMT
Example by considering an average dead anatomical volume of 150 ml
Example / curve A
breath Profile : 2.5 L in 5 s , constant breath
Dead volume = 150 mL
3rd Committee Draft Recommendation on Breath Alcohol Analysers
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TC 17/SC 7: Breath Alcohol Analysers
August 2007
simulation of a curve C (%) = f(t)
breath 2.5 L in 5 s ; flow rate = 0.5 L/s ; dead volume = 150 mL
plateau reached for a concentration = 99.0 % after 2.0 s
Concentration (%
100.00
80.00
60.00
40.00
20.00
0.00
0
1
2
3
4
5
time (s)
Concentration (%)
Example / curve B
breath Profile : 2.0 L in 5 s , constant breath
Dead volume = 150 mL
simulation of curve C (%) = f (t)
breath 2 L in 5 s ; flow rate = 0.4 L/s ; dead volume = 150 mL
plateau reached for a concentration = 99.0 % after 1.7 s
Concentration (%
100.00
80.00
60.00
40.00
20.00
0.00
0
1
2
3
4
5
Temps (s)
Concentration (%)
Example by considering an average dead anatomical volume of 300 ml
Example / curves C
3rd Committee Draft Recommendation on Breath Alcohol Analysers
Page 34 /37
TC 17/SC 7: Breath Alcohol Analysers
August 2007
breath : Profile 2.5 L in 5 s , constant breath
Dead volume = 300 mL
simulation of a curve C (%) = f(t)
breath 2.5 L in 5 s ; flow rate = 0.5 L/s ; dead volume = 300 mL
plateau reached for a concentration = 99.0 % after 2.7 s
Concentration (%
100.00
80.00
60.00
40.00
20.00
0.00
0
1
2
3
4
5
time (s)
Concentration (%)
Example / curves D
breath Profile : 2.0 L in 5 s , constant breath
Dead volume = 300 mL
3rd Committee Draft Recommendation on Breath Alcohol Analysers
Page 35 /37
TC 17/SC 7: Breath Alcohol Analysers
August 2007
simulation of curve C (%) = f (t)
breath 2 L in 5 s ; flow rate = 0.4 L/s ; dead volume = 300 mL
plateau reached for a concentration = 99.0 % after 3.5 s
Concentration (%
100.00
80.00
60.00
40.00
20.00
0.00
0
1
2
3
4
5
Temps (s)
Concentration (%)
Proposal for the next draft :
Confirmation of the mathematical model and qualitative information on the determination of the
plateau.
Example of a curve of alcohol concentration as a function of time obtained on simulation test bench.
recording of the curve of alcohol concentration (expressed in % ) according to time;
breath 3 L in 5 s ; dead volume 150 mL ; plate reached in 2.5 s for 99.5 % of alcohol
120.00
alcohol concentration (%)
100.00
80.00
60.00
40.00
20.00
0.00
0
1
2
3
4
5
time of exhalation (s)
3rd Committee Draft Recommendation on Breath Alcohol Analysers
Page 36 /37
TC 17/SC 7: Breath Alcohol Analysers
August 2007
Annexe D
Test Report Format
To be developed when the list of test is finalised.
3rd Committee Draft Recommendation on Breath Alcohol Analysers
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